Class: MCP::Server

Inherits:
Object
  • Object
show all
Includes:
Instrumentation
Defined in:
lib/mcp/server.rb,
lib/mcp/server/capabilities.rb,
lib/mcp/server/transports/stdio_transport.rb,
lib/mcp/server/transports/streamable_http_transport.rb

Defined Under Namespace

Modules: Transports Classes: Capabilities, MethodAlreadyDefinedError, RequestHandlerError

Constant Summary collapse

DEFAULT_VERSION = 
"0.1.0"

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods included from Instrumentation

#add_instrumentation_data, #instrument_call

Constructor Details

#initialize(name: "model_context_protocol", title: nil, version: DEFAULT_VERSION, instructions: nil, tools: [], prompts: [], resources: [], resource_templates: [], server_context: nil, configuration: nil, capabilities: nil, transport: nil) ⇒ Server

Returns a new instance of Server.



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# File 'lib/mcp/server.rb', line 36

def initialize(
  name: "model_context_protocol",
  title: nil,
  version: DEFAULT_VERSION,
  instructions: nil,
  tools: [],
  prompts: [],
  resources: [],
  resource_templates: [],
  server_context: nil,
  configuration: nil,
  capabilities: nil,
  transport: nil
)
  @name = name
  @title = title
  @version = version
  @instructions = instructions
  @tools = tools.to_h { |t| [t.name_value, t] }
  @prompts = prompts.to_h { |p| [p.name_value, p] }
  @resources = resources
  @resource_templates = resource_templates
  @resource_index = index_resources_by_uri(resources)
  @server_context = server_context
  @configuration = MCP.configuration.merge(configuration)

  validate!

  @capabilities = capabilities || default_capabilities

  @handlers = {
    Methods::RESOURCES_LIST => method(:list_resources),
    Methods::RESOURCES_READ => method(:read_resource_no_content),
    Methods::RESOURCES_TEMPLATES_LIST => method(:list_resource_templates),
    Methods::TOOLS_LIST => method(:list_tools),
    Methods::TOOLS_CALL => method(:call_tool),
    Methods::PROMPTS_LIST => method(:list_prompts),
    Methods::PROMPTS_GET => method(:get_prompt),
    Methods::INITIALIZE => method(:init),
    Methods::PING => ->(_) { {} },
    Methods::NOTIFICATIONS_INITIALIZED => ->(_) {},

    # No op handlers for currently unsupported methods
    Methods::RESOURCES_SUBSCRIBE => ->(_) {},
    Methods::RESOURCES_UNSUBSCRIBE => ->(_) {},
    Methods::COMPLETION_COMPLETE => ->(_) {},
    Methods::LOGGING_SET_LEVEL => ->(_) {},
  }
  @transport = transport
end

Instance Attribute Details

#capabilities ⇒ Object

Returns the value of attribute capabilities.



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# File 'lib/mcp/server.rb', line 34

def capabilities
  @capabilities
end

#configuration ⇒ Object

Returns the value of attribute configuration.



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# File 'lib/mcp/server.rb', line 34

def configuration
  @configuration
end

#instructions ⇒ Object

Returns the value of attribute instructions.



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# File 'lib/mcp/server.rb', line 34

def instructions
  @instructions
end

#name ⇒ Object

Returns the value of attribute name.



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# File 'lib/mcp/server.rb', line 34

def name
  @name
end

#prompts ⇒ Object

Returns the value of attribute prompts.



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# File 'lib/mcp/server.rb', line 34

def prompts
  @prompts
end

#resources ⇒ Object

Returns the value of attribute resources.



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# File 'lib/mcp/server.rb', line 34

def resources
  @resources
end

#server_context ⇒ Object

Returns the value of attribute server_context.



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# File 'lib/mcp/server.rb', line 34

def server_context
  @server_context
end

#title ⇒ Object

Returns the value of attribute title.



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# File 'lib/mcp/server.rb', line 34

def title
  @title
end

#tools ⇒ Object

Returns the value of attribute tools.



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# File 'lib/mcp/server.rb', line 34

def tools
  @tools
end

#transport ⇒ Object

Returns the value of attribute transport.



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# File 'lib/mcp/server.rb', line 34

def transport
  @transport
end

#version ⇒ Object

Returns the value of attribute version.



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# File 'lib/mcp/server.rb', line 34

def version
  @version
end

Instance Method Details

#define_custom_method(method_name:, &block) ⇒ Object 



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# File 'lib/mcp/server.rb', line 111

def define_custom_method(method_name:, &block)
  if @handlers.key?(method_name)
    raise MethodAlreadyDefinedError, method_name
  end

  @handlers[method_name] = block
end

#define_prompt(name: nil, title: nil, description: nil, arguments: [], &block) ⇒ Object 



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# File 'lib/mcp/server.rb', line 106

def define_prompt(name: nil, title: nil, description: nil, arguments: [], &block)
  prompt = Prompt.define(name:, title:, description:, arguments:, &block)
  @prompts[prompt.name_value] = prompt
end

#define_tool(name: nil, title: nil, description: nil, input_schema: nil, annotations: nil, meta: nil, &block) ⇒ Object 



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# File 'lib/mcp/server.rb', line 99

def define_tool(name: nil, title: nil, description: nil, input_schema: nil, annotations: nil, meta: nil, &block)
  tool = Tool.define(name:, title:, description:, input_schema:, annotations:, meta:, &block)
  @tools[tool.name_value] = tool

  validate!
end

#handle(request) ⇒ Object 



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# File 'lib/mcp/server.rb', line 87

def handle(request)
  JsonRpcHandler.handle(request) do |method|
    handle_request(request, method)
  end
end

#handle_json(request) ⇒ Object 



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# File 'lib/mcp/server.rb', line 93

def handle_json(request)
  JsonRpcHandler.handle_json(request) do |method|
    handle_request(request, method)
  end
end

#notify_prompts_list_changed ⇒ Object 



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# File 'lib/mcp/server.rb', line 127

def notify_prompts_list_changed
  return unless @transport

  @transport.send_notification(Methods::NOTIFICATIONS_PROMPTS_LIST_CHANGED)
rescue => e
  report_exception(e, { notification: "prompts_list_changed" })
end

#notify_resources_list_changed ⇒ Object 



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# File 'lib/mcp/server.rb', line 135

def notify_resources_list_changed
  return unless @transport

  @transport.send_notification(Methods::NOTIFICATIONS_RESOURCES_LIST_CHANGED)
rescue => e
  report_exception(e, { notification: "resources_list_changed" })
end

#notify_tools_list_changed ⇒ Object 



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# File 'lib/mcp/server.rb', line 119

def notify_tools_list_changed
  return unless @transport

  @transport.send_notification(Methods::NOTIFICATIONS_TOOLS_LIST_CHANGED)
rescue => e
  report_exception(e, { notification: "tools_list_changed" })
end

#prompts_get_handler(&block) ⇒ Object 



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# File 'lib/mcp/server.rb', line 167

def prompts_get_handler(&block)
  @handlers[Methods::PROMPTS_GET] = block
end

#prompts_list_handler(&block) ⇒ Object 



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# File 'lib/mcp/server.rb', line 163

def prompts_list_handler(&block)
  @handlers[Methods::PROMPTS_LIST] = block
end

#resources_list_handler(&block) ⇒ Object 



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# File 'lib/mcp/server.rb', line 143

def resources_list_handler(&block)
  @handlers[Methods::RESOURCES_LIST] = block
end

#resources_read_handler(&block) ⇒ Object 



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# File 'lib/mcp/server.rb', line 147

def resources_read_handler(&block)
  @handlers[Methods::RESOURCES_READ] = block
end

#resources_templates_list_handler(&block) ⇒ Object 



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# File 'lib/mcp/server.rb', line 151

def resources_templates_list_handler(&block)
  @handlers[Methods::RESOURCES_TEMPLATES_LIST] = block
end

#tools_call_handler(&block) ⇒ Object 



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# File 'lib/mcp/server.rb', line 159

def tools_call_handler(&block)
  @handlers[Methods::TOOLS_CALL] = block
end

#tools_list_handler(&block) ⇒ Object 



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# File 'lib/mcp/server.rb', line 155

def tools_list_handler(&block)
  @handlers[Methods::TOOLS_LIST] = block
end